Space reactor benchmarks

If you want power in deep space or deep underneath a vacuum lowgrav planetoid, you need a nuclear reactor. ToughSF has been posting on some of the more-theoretical ideas.

Pluta and Morata has this in 2012. With the original 4.2% efficient thermionic converters, this would mean 161 W/kg, but with a 20% efficient 'dynamic' converter and fuel load reduced to 3 years, 866 W/kg is possible. (That's alpha=1.155, considered excellent, honestly better than a nuclear submarine.) 25-200 MW.

Nathaniel Read submitted a PhD Thesis in 2020 (pdf): 89 W/kg for 1 MWe, for 7 years. Although at 1300K we suppose it should be easier to insulate - and to insure. ToughSF commiserated that the cold was making this as inefficient as it is.

I suspect solar-energy is a competitor for all of these up to Mars' orbit. Also, to boost a spacecraft to (say) Uranus. But outside 3 AU or so, maybe it's good for de-celeration on the VASIMR plan.